Skilled improvisers are able to shape in real time a music discourse by continuously modulating pitch, rhythm, tempo and loudness to communicate high-level information such as musical structures and emotion.

Most people think what could I do, I think what shouldn't I do. What I should do perhaps is involved with the fact that I'm Jewish and what is known as Jewish paranoia. I don't feel comfortable enough to feel that everything is on my side and that it's going to work just the way I want it.
--Morton Feldman